what other than the wrong powder causes these signs?

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Oil in the chamber didn't cause the the fired primer to fall out of the case.

That, and the clear impression of the ejecter hole in the bolt face on the case head can only be caused by a way over-pressure load.

I agree if the Prvi Partizan brass doesn't have way less capacity then what he was using before, the scale was probably set wrong.

rc
 
in ref to the primer, I will say that I was kinda wondering if that might happen eventually. since the effort involved in primer seating was, inconsistent. I use a LEE Auto-prime and with most of the PPU brass primer seating has been typical to a bit stiff, a few though (3-4 out of 50) the primer went in a little too easy to be frank

obviously still open to other info/possibilities, but as of right now i think i'm dealing with a scale issue and a bad piece of brass (for the blown primer).

will do some "forensic work" on my remaining loads this evening.
 
How much does that PP case weigh? Weigh a case and I will tell you if it is thicker than a Winchester, Remington or Federal case.
 
Kinda looks to me like its more the flash hole. I had some mil surp brass that I full length sized and they were burning out around the pimer throught the pocket. Either that or maybe the primer pockets are worn uneven from a pocket cleaning tool, that happens with my 7mag brass. Do the primrs fit tight?
 
thanks for the info and sugestions so far guys. Unfortunately somethings have come up in the rest of my life, that i need to take care fo before i can et back to anything to do with firearms, or any of my other hobbies. :banghead:

so, I WILL get back to this, but it's gonna be a week or so.
 
I think too much powder, due to issues with the scale. I cant think of anything else that would blow out a primer.
 
I have seen PRVI cases around but frankly I know nothing about them. However given all the facts, I have to assume(and could be wrong) that these are either military cases or cases with less internal volume than American made 308 cases and therefore less volume would definitely increase pressure and those cases do show signs of high pressure. I would weigh several of these cases filled to capacity with water and then weigh a standard case the same way to compare weights(volume), and if you can, tare your empty cases to zero or weigh the contents separately. I think you may be very surprised on your findings. I would either reduce my starting load by at least 10% or scrap these cases and buy some Remington or Winchester cases. Be safe and don't shoot any more of your starting loads!
 
little bit of an update.

I've decided to operate on the assuption that my scale was out of whack. In part since the previous set of loads i did, that did not exhibit pressure signs, were 41.0-41.5grs.

on the subject of case capacity, these cases have noticably less capacity than LC (ie known mil-spec) brass, but not vastly less. just that side by side you can see that the top of the charge is lower in the PP case. in the LC cases i would Definitely have to use a further reduced starting charge, i'd be afraid that a 175smk seated to a COL of 2.80" would be a slightly compressed load in the Lake City cases.

so i'm going to give this one more try with a different and freshly calibrated scale, using the 41gr load and see what happens. if i get signs this time, i'm changing powders and tossing the 4895 i have left.
 
Unless you are talking about the ring around the firing pin, that primer does not look like too high pressure. Its hard to tell from the picture if its just a mark or actually protruding more than a few 1/1000s The other mark is your ejector pin. Maybe it got trash behind it or something.
 
I shoot that exact same load with both Lapua and Winchester brass and have never had a high pressure issue. I would not suspect the load unless the scale was whacked, as previously mentioned.

The firing pin hole on my rifle (same as yours, 700 sps varmint) is loose as well, I get minor flowing at very mild loads. Yours is worse than mine has ever been.

I'm going to put my verdict in for a touch of oil in the chamber causing the extractor marks, and loose primer pockets causing the one to fall out.

Any chance you remember if the load felt really hot when you shot it?
 
That load is perfectly safe in all my rifles.

Trim your brass to 2.00 inches. Keep the case mouths away from the throat. Even though you are trimming "below max", you are only a couple of thousands from max. Better be .015 from max.

I can tell you that nothing bad happens if you trim way below minimum. But case necks in throat, even by a little bit, bad things will happen.

However, I suspect that you put in more powder than you think.

I have check weights and use them on my scales all the time.

I think oil in the chamber has pushed the cartridge back against the bolt leaving the impression.
I think your fireing pin hole is on the large side allowing for primer flow.
I don't think you are seeing high pressure signs as your primer looks rather normal.
Click to expand...

I have liberally coated cases with motor oil and never saw pressure indications on normally loaded cartridges. Blown primers are a positive indication of too high of pressures. Case head flow into the extractor groove is another indication of high pressures.

Unless the primer is blown, you really can't tell pressures. Primers Lie.:evil:
 
Any chance you remember if the load felt really hot when you shot it?
Click to expand...

I don't remember these loads being especially "lively". then again for recoil from firearms chambered for greater than .223 in general and .308 in specific my personal "expereince based benchmark" is the little pre-Mohawk model 600 that was my intro to rifles chambered for "full power" rounds. and that gun "killed on both ends" so to speak, .308 in a rifle lighter than many people's target style 10/22s.:uhoh:

hopefully i'll be able to try out the fresh batch later today, depends on weather, range availability (with a silhouette match on the main rifle range today, the secondary 100yd area maybe crowded), and whether i can get a nap between now and noon.
 
based on the experience i had today, I'm pretty much positive that this was a brass issue.
I know that some of the primer pockets were on the loose side and that is a very viable explanation for the two blown primers.
Beyound that I realized that,
  1. ALL of the brass that has stuck in the chamber was on it's 2nd run through the reloading process
  2. even when i was factory new, the Prvi Partizan ammo/brass was difficult to extract, and a few round were stiff on chambering
  3. I never expereinced any issues in chambering or extraction with any of the winchester or LC based ammo i've run through this rifle (only purchased the PPU because my stock of LC and Win was too low)
  4. the 10 rounds i made up using this same load in Winchester brass (only have 20pcs. used the Win brass to use up the small amount of powder left) likewise had no issues

so at this point I have decided to de-prime and most likely sell my remaining Prvi brass to the scrap man for a few bucks. and then start over with Winchester or similar commercial brass.
 
Have you fired any factory loaded ammo, or the same load with different brass since you first posted? Just to rule out something being wrong with the rifle (no idea what that would be though)
 
Have you fired any factory loaded ammo, or the same load with different brass since you first posted? Just to rule out something being wrong with the rifle (no idea what that would be though)
Click to expand...

Yes as Noted:
the 10 rounds i made up using this same load in Winchester brass (only have 20pcs. used the Win brass to use up the small amount of powder left) likewise had no issues
Click to expand...

in the past year i've run three different brands of brass through this rifle,
  1. 20rds Winchester (factory hunting fodder) this is of course the source of the comparison brass from yesterday. No issues at any time

  2. 50rds of Georgia Arms 168gr "Match" on LC brass, mixed brass lots including some of the Knurled base cases, bought circa '95 came in a heavy plastic heat seal bag. 10 or so out of 50 suffered split cases of varying severity. but nothing traceable to the rifle, the case failures were typical of old, abused, been reloaded one time too many cases

  3. 140rds/pieces Prvi Partizan originally as factory 175gr "Match" ammo (crap, uses 175gr FMJ), the best i can say for this stuff is that when factory fresh it all fed, and all went boom. but even on it's first firing (fresh from factory) some of the cases showed sticky extraction, when reloaded the primer pockets varied in "tightness" (i use a hand priming tool, i can feel the difference), and after bieng neck sized.. well that's why this thread exists, for me this brass/ammo has been utter garbage.

Oh i've also run 3 or 4 rounds of factory or full-length sized handload, borrowed from fellow shooters just to make sure.

at this point the Prvi is the only brand that has given me continued trouble (can't bring myself to blame the G.A. stuff for the split necks etc, since it was cheap to begin with, and improperly stored for at least a portion of the 14 years it sat in my ammo stash before being fired.)

and now i'm off to houston with pen and pad to see how much the locals are charging for the components i need. powder i know i'll get local (houston), but the next batch of bullets and the replacement batch of brass I might get off the net.
 
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Soft brass.

What if the brass was way too soft? That could certainly cause the flow into the ejector cutout (I've seen it with Federal brass many times).
 
What if the brass was way too soft? That could certainly cause the flow into the ejector cutout (I've seen it with Federal brass many times).
Click to expand...

that's pretty much been my conclusion at this point. that the brass is so soft it's effectively useless.
 
From my 40+ years experince of reloading, it looks like a powder problem, a under load can and will cause that problem and a over load will do the same thing. Check out your scale and see it they are working properly. A electronic scale can be thrown of by a few factors also, draft, phosphorescent lighting. not being warmed up before you set the scales up!
And yes this has happened to me over the last 40+ years!
 
I'm visually impaired and may have missed this point if someone else made it........but how the cases were powdered could be the cause. Sometimes if throwing charges with a powder measure, a dump may not be complete and the next charge will be heavy. Tubular powders are prone to do this if ever so slightly damp or a little oil or grease gets into the measure's throat. From the photos of the cases, I'd say the left one is pretty hot and the blown primer and enlarged pocket would have taken at least 75,000 psi or more. One last thought, could the case have been annealed somehow? Just thank God you were using a stout bolt action and not a break open action like H&R. If you weighed every charge then the only factor I see coming in play is the bullet seated out too far as previously said. Could be other causes but I think those here have pretty well covered them.
ancient rifle man
gunsmith for over 50 years.
 
I assume you use calibration weights to set your powder measure? If you don't, you'd be surprised how much your actual weights can vary...you can't depend on the scale notations.

Also, IMR 4895 and H-4895 aren't equivalent...the IMR will give somewhat greater pressure for the same weight...
 
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